1. Field of the Invention
The present invention relates to a printing apparatus, a printing control method, and a program for implementing the method, and more particularly to a printing apparatus and a printing control method applied to an inkjet recording apparatus, which are capable of electrically and mechanically adjusting the gap between a recording head and a recording medium (hereinafter referred to as “the head-sheet gap”) using a driving means such as a motor, as well as a program for implementing the printing control method.
2. Description of the Related Art
Conventionally, to adjust the head-sheet gap in an inkjet recording apparatus which prints (records) an image on a recording medium by discharging ink from a recording head to cause the ink to attach to the recording medium, there has been widely used a method in which the user adjusts the head-sheet gap by manually operating a head-sheet gap-adjusting lever, which is provided in the main body of the ink jet recording apparatus (refer to Japanese Laid-Open Patent Publication (Kokai) No. H08-118762, for example).
The reasons why the head-sheet gap is adjusted in the inkjet recording apparatus are as follows.
(1) If a variation in the head-sheet gap due to a difference in thickness of recording media is eliminated by adjustment, printing can be properly performed to obtain a stable image; and
(2) Even if the head-sheet gap is properly set, a recording medium itself may ripple or warp during printing due to e.g. environmental changes. Then, the recording medium becomes tainted since the recording head rubs the recording medium, but this can be avoided by adjusting the head-sheet gap.
However, with functional improvement of the inkjet recording apparatus, it has become possible to provide the inkjet recording apparatus with a driving means such as a motor serving as a mechanism for adjusting the head-sheet gap so that the head-sheet gap can be electrically and mechanically adjusted via the driving means (refer to Japanese Laid-Open Patent Publication (Kokai) No. 2001-162889, for example).
Thus, in the conventional inkjet recording apparatus, it is possible to adjust the gap between the recording head and the recording medium, i.e. the head-sheet gap.
Further, in recent years, to reduce costs, there has been developed an inkjet recording apparatus which does not require a head-sheet gap-adjusting lever. In this inkjet recording apparatus, for example, the user electrically and mechanically adjusts the head-sheet gap via the above-mentioned driving means according to the type of a recording medium set through a user interface of a printer driver on a host computer connected to the inkjet recording apparatus.
FIG. 10 is a view showing an example of the user interface on a print setting screen of the printer driver.
As shown in FIG. 10, the user can set the type of sheet by selecting a desired setting value from a selection menu in FIG. 11 as an item in a selection field 1001 for designating the type of sheet as a recording medium. Then, according to the set type of the sheet, a suitable head-sheet gap is selected and output as a command in a print job. Therefore, it is possible to set suitable head-sheet gaps in advance for respective types of sheets. Also, the user can select a setting value indicative of a feeding method: “auto feeder” or “ASF (rub preventing)” in a feeding method selection field 1002. The “ASF (rub preventing)” represents a feeding method intended to set a wider head-sheet gap than in normal printing. By setting the “ASF (rub preventing)” as a feeding method via the user interface (FIG. 10) of the printer driver when instructing to perform printing, the user can instruct to perform printing with a wider head-sheet gap than a head-sheet gap corresponding to a setting value selected in the sheet type selection field 1001 in a print job process corresponding to the printing instruction. This makes it possible to prevent a printing sheet as a recording medium from being rubbed.
With the above inkjet recording apparatus which is capable of electrically and mechanically adjusting the head-sheet gap when the user selects a setting value in the sheet type selection field 1001 or the feeding method selection field 1002 on the user interface of the printer driver, a “head-sheet gap designation command” which designates the heads-sheet gap (“wide” or “narrow”) for one printing (hereinafter referred to as “one print job”), which is designated by the user through operation of the host computer, can be issued from the host computer at least once to the inkjet recording apparatus, so that the head-sheet gap can be adjusted
According to this method, since the head-sheet gap designation command is designated according to a setting, e.g. the type of recording medium, made by the user for the printer driver on the host computer, a specification change due to e.g. the addition of a new recording medium or a change in the material of a recording medium in settings of the printer driver can be coped with only by allotting the head-sheet gap designating command to the recording medium which has been added or changed in material. Therefore, it is relatively easy to cope with such a specification change by version upgrade of the printer driver.
Further, a problem that the recording head and a recording medium rub each other due to e.g. environmental changes although the recording medium is a type that should be printed with a narrow head-sheet gap can be solved by providing a switch or the like which forces the head-sheet gap to be widened (“AFS (rub preventing)” as a feeding method) on the user interface of the printer driver, so that a head-sheet gap designating command which designates a “wide” head-sheet gap is issued once for one print job when the user turns on the switch.
Conventionally, in the case where an image taken by e.g. a digital camera is printed using the inkjet recording apparatus, it has been generally carried out to connect the digital camera and a host computer to each other via an interface such as a USB (Universal Serial Bus) to temporarily load the image taken by the digital camera into the host computer, and then transfer the image from the host computer to the inkjet recording apparatus so that the image can be printed.
In recent years, however, the inkjet recording apparatus has been further improved in terms of functions. For example, in recent years, there has been developed an inkjet recording apparatus which is provided with a second interface other than the interface connected to the host computer, and is connected directly to a digital camera via the second interface to support a camera direct printing function which enables printing without a host computer.
If the above described method in which a head-sheet gap designating command is issued once for one print job is applied to the inkjet recording apparatus which has the camera direct printing function which enables printing without a host computer, it is necessary to issue the head-sheet gap designating command from the digital camera, which raises the problem that items which should be originally set through operation of the inkjet recording apparatus must be set through operation of the digital camera.
Also, according to the camera direct printing function, firmware of the digital camera or the inkjet recording apparatus must be updated so as to cope with a specification change due to e.g. the addition of a new recording medium or a change in the material of a recording medium in settings made through the printer driver as described above, and this is more difficult as compared with update of the printer driver since it is now desired to support the camera direct printing function through operation of digital cameras with different specifications.